- •11.1 Cooling
- •Table 11.2 Molecular Lowering of the Melting or Freezing Point
- •11.2 Drying and Humidification
- •11.3 Boiling Points and Heating Baths
- •Table 11.8 Organic Solvents Arranged by Boiling Points
- •Table 11.9 Molecular Elevation of the Boiling Point
- •11.4 Separation Methods
- •Table 11.11 Solvents of Chromatographic Interest
- •11.4.1 McReynolds’ Constants
- •11.4.2 Chromatographic Behavior of Solutes
- •11.4.3 Ion-Exchange (Normal Pressure, Columnar)
- •Table 11.16 Guide to Ion-Exchange Resins
- •Table 11.18 Relative Selectivity of Various Counter Anions
- •11.5 Gravimetric Analysis
- •Table 11.19 Gravimetric Factors
- •Table 11.20 Elements Precipitated by General Analytical Reagents
- •Table 11.21 Cleaning Solutions for Fritted Glassware
- •Table 11.25 Tolerances for Analytical Weights
- •Table 11.26 Heating Temperatures, Composition of Weighing Forms, and Gravimetric Factors
- •11.6 Volumetric Analysis
- •Table 11.28 Titrimetric (Volumetric) Factors
- •11.6.3 Standard Volumetric (Titrimetric) Redox Solutions
- •11.6.4 Indicators for Redox Titrations
- •11.6.5 Precipitation Titrations
- •11.6.6 Complexometric Titrations
- •11.6.7 Masking Agents
- •11.6.8 Demasking
- •Table 11.30 Standard Solutions for Precipitation Titrations
- •Table 11.31 Indicators for Precipitation Titrations
- •Table 11.32 Properties and Applications of Selected Metal Ion Indicators
- •Table 11.41 Pipet Capacity Tolerances
- •Table 11.43 Buret Accuracy Tolerances
- •11.7 Laboratory Solutions
- •11.7.1 General Reagents, Indicators, and Special Solutions
- •Table 11.49 TLV Concentration Limits for Gases and Vapors
- •Table 11.52 Chemicals Which Polymerize or Decompose on Extended Refrigeration
- •11.9 Thermometry
- •11.9.1 Temperature and Its Measurement
- •11.10 Thermocouples
- •Table 11.63 Type T Thermocouples: Copper vs. Copper-Nickel Alloy
- •11.11 Correction for Emergent Stem of Thermometers
SECTION 11
PRACTICAL LABORATORY
INFORMATION
11.1 |
COOLING |
|
11.3 |
Table 11.1 |
Cooling Mixtures |
11.3 |
|
Table 11.2 Molecular Lowering of the Melting or Freezing Point |
11.4 |
||
11.2 |
DRYING AND HUMIDIFICATION |
11.5 |
|
Table 11.3 |
Drying Agents |
11.5 |
|
Table 11.4 Solutions for Maintaining Constant Humidity |
11.6 |
||
Table 11.5 Concentration of Solutions of H2SO4, NaOH, and CaCl2 Giving |
|
||
|
|
Specified Vapor Pressures and Percent Humidities at 25 C |
11.7 |
Table 11.6 Relative Humidity from Wet and Dry Bulb Thermometer Readings |
11.8 |
||
Table 11.7 Relative Humidity from Dew Point Readings |
11.9 |
||
11.3 BOILING POINTS AND HEATING BATHS |
11.10 |
||
Table 11.8 Organic Solvents Arranged by Boiling Points |
11.10 |
||
Table 11.9 Molecular Elevation of the Boiling Point |
11.13 |
||
Table 11.10 Substances Which Can Be Used for Heating Baths |
11.15 |
||
11.4 |
SEPARATION METHODS |
11.16 |
|
Table 11.11 |
Solvents of Chromatographic Interest |
11.16 |
|
Table 11.12 Solvents Having the Same Refractive Index and the Same Density |
|
||
|
|
at 25 C |
11.18 |
Table 11.13 McReynolds’ Constants for Stationary Phases in Gas |
|
||
|
|
Chromatography |
11.21 |
11.4.1 |
McReynolds’ Constants |
11.26 |
|
Table 11.14 Characteristics of Selected Supercritical Fluids |
11.26 |
||
11.4.2 |
Chromatographic Behavior of Solutes |
11.27 |
|
Table 11.15 Typical Performances in HPLC for Various Conditions |
11.31 |
||
11.4.3 |
Ion-Exchange (Normal Pressure, Columnar) |
11.32 |
|
Table 11.16 Guide to Ion-Exchange Resins |
11.33 |
||
Table 11.17 Relative Selectivity of Various Counter Cations |
11.37 |
||
Table 11.18 Relative Selectivity of Various Counter Anions |
11.38 |
||
11.5 |
GRAVIMETRIC ANALYSIS |
11.41 |
|
Table 11.19 |
Gravimetric Factors |
11.41 |
|
Table 11.20 Elements Precipitated by General Analytical Reagents |
11.67 |
||
Table 11.21 Cleaning Solutions for Fritted Glassware |
11.69 |
||
Table 11.22 |
Common Fluxes |
11.70 |
|
Table 11.23 |
Membrane Filters |
11.70 |
|
Table 11.24 Porosities of Fritted Glassware |
11.71 |
||
Table 11.25 |
Tolerances for Analytical Weights |
11.71 |
|
Table 11.26 Heating Temperatures, Composition of Weighing Forms, and |
|
||
|
|
Gravimetric Factors |
11.72 |
11.6 |
VOLUMETRIC ANALYSIS |
11.74 |
|
11.6.1 |
Acid-Base Titrations in Aqueous Media |
11.74 |
|
Table 11.27 Primary Standards for Aqueous Acid-Base Titrations |
11.74 |
||
Table 11.28 |
Titrimetric (Volumetric) Factors |
11.76 |
|
11.6.2 Titrimetric (Volumetric) Factors for Acid-Base Titrations |
11.82 |
||
11.6.3 Standard Volumetric (Titrimetric) Redox Solutions |
11.82 |
||
11.6.4 |
Indicators for Redox Titrations |
11.83 |
|
Table 11.29 Equations for the Redox Determinations of the Elements with |
|
||
|
|
Equivalent Weights |
11.84 |
11.1
11.2 |
|
SECTION 11 |
|
11.6.5 |
Precipitation Titrations |
11.89 |
|
11.6.6 |
Complexometric Titrations |
11.89 |
|
11.6.7 |
Masking Agents |
11.92 |
|
11.6.8 |
Demasking |
11.93 |
|
Table 11.30 Standard Solutions for Precipitation Titrations |
11.94 |
||
Table 11.31 Indicators for Precipitation Titrations |
11.95 |
||
Table 11.32 Properties and Applications of Selected Metal Ion Indicators |
11.96 |
||
Table 11.33 Variation of 4 with pH |
11.97 |
||
Table 11.34 Formation Constants of EDTA Complexes at 25 C, Ionic Strength |
|
||
|
|
Approaching Zero |
11.97 |
Table 11.35 Cumulative Formation Constants of Ammine Complexes at 20 C, |
|
||
|
|
Ionic Strength 0.1 |
11.97 |
Table 11.36 Masking Agents for Various Elements |
11.98 |
||
Table 11.37 Masking Agents for Anions and Neutral Molecules |
11.100 |
||
Table 11.38 Common Demasking Agents |
11.100 |
||
Table 11.39 Amino Acids pI and pKa Values |
11.102 |
||
Table 11.40 |
Tolerances of Volumetric Flasks |
11.102 |
|
Table 11.41 |
Pipet Capacity Tolerances |
11.103 |
|
Table 11.42 |
Tolerances of Micropipets (Eppendorf) |
11.103 |
|
Table 11.43 Buret Accuracy Tolerances |
11.103 |
||
Table 11.44 Factors for Simplified Computation of Volume |
11.104 |
||
Table 11.45 Cubical Coefficients of Thermal Expansion |
11.105 |
||
Table 11.46 General Solubility Rules for Inorganic Compounds |
11.105 |
||
11.7 |
LABORATORY SOLUTIONS |
11.106 |
|
Table 11.47 Concentration of Commonly Used Acids and Bases |
11.106 |
||
Table 11.48 |
Standard Stock Solutions |
11.107 |
|
11.7.1 General Reagents, Indicators, and Special Solutions |
11.109 |
||
Table 11.49 TLV Concentration Limits for Gases and Vapors |
11.121 |
||
Table 11.50 Some Common Reactive and Incompatible Chemicals |
11.130 |
||
Table 11.51 Chemicals Recommended for Refrigerated Storage |
11.136 |
||
Table 11.52 Chemicals Which Polymerize or Decompose on Extended |
|
||
|
|
Refrigeration |
11.136 |
11.8 |
SIEVES AND SCREENS |
11.137 |
|
Table 11.53 U.S. Standard Sieve Series |
11.137 |
||
11.9 |
THERMOMETRY |
11.137 |
|
11.9.1 |
Temperature and Its Measurement |
11.137 |
|
Table 11.54 Fixed Points in the ITS-90 |
11.138 |
||
11.10 |
THERMOCOUPLES |
11.138 |
|
Table 11.55 |
Thermoelectric Values in Millivolts at Fixed Points for Various |
|
|
|
|
Thermocouples |
11.140 |
Table 11.56 Type B Thermocouples: Platinum–30% Rhodium Alloy vs. |
|
||
|
|
Platinum–6% Rhodium Alloy |
11.142 |
Table 11.57 Type E Thermocouples: Nickel-Chromium Alloy vs. Copper-Nickel |
|
||
|
|
Alloy |
11.143 |
Table 11.58 Type J Thermocouples: Iron vs. Copper-Nickel Alloy |
11.144 |
||
Table 11.59 Type K Thermocouples: Nickel-Chromium Alloy vs. Nickel- |
|
||
|
|
Aluminum Alloy |
11.145 |
Table 11.60 Type N Thermocouples: Nickel–14.2% Chromium–1.4% Silicon |
|
||
|
|
Alloy vs. Nickel–4.4% Silicon–0.1% Magnesium Alloy |
11.146 |
Table 11.61 Type R Thermocouples: Platinum–13% Rhodium Alloy vs. Platinum |
11.147 |
||
Table 11.62 Type S Thermocouples: Platinum–10% Rhodium Alloy vs. Platinum |
11.148 |
||
Table 11.63 Type T Thermocouples: Copper vs. Copper-Nickel Alloy |
11.149 |
||
11.11 CORRECTION FOR EMERGENT STEM OF THERMOMETERS |
11.150 |
||
Table 11.64 Values of K for Stem Correction of Thermometers |
11.150 |
|
PRACTICAL |
LABORATORY |
INFORMATION |
|
|
|
11.3 |
11.1 COOLING |
|
|
|
|
|
|
|
TABLE 11.1 |
Cooling Mixtures |
|
|
|
|
|
|
The table below gives the lowest temperature that can be obtained from a mixture of the inorganic salt with |
|
||||||
finely shaved dry ice. With the organic substances, dry ice ( |
|
78 C) in small lumps can be added to the solvent |
|
||||
until a slight excess of dry ice remains or liquid nitrogen ( |
196 C) can be poured into the solvent until a slush |
|
|||||
is formed that consists of the solid-liquid mixture at its melting point. |
|
|
|||||
|
|
|
|
|
|
|
|
|
|
|
Quantity of |
|
Quantity of |
Temperature, |
|
|
Substance |
|
substance, g |
|
water, mL |
C |
|
|
|
|
|
|
|
|
|
|
Ammonium nitrate |
100 |
94 |
4.0 |
|
||
|
Sodium nitrate |
|
75 |
100 |
5.3 |
|
|
|
Sodium thiosulfate 5-water |
110 |
100 |
8.0 |
|
||
|
Sodium chloride |
|
36 |
100 |
10.0 |
|
|
|
Sodium nitrate |
|
50 |
100 |
17.8 |
|
|
|
Sodium bromide |
|
66 |
100 |
28 |
|
|
|
Magnesium chloride |
85 |
100 |
34 |
|
||
|
Calcium chloride 6-water |
100 |
81 |
40.3 |
|
||
|
|
|
100 |
70 |
55 |
|
|
|
|
|
|
|
|
|
|
Substance |
Temperature, |
C |
|
Substance |
Temperature, |
C |
|
|
|
|
|
|
|
|
|
Ethylene glycol |
|
13 |
|
|
Acetone |
77 |
|
1,2-Dichlorobenzene |
17 |
|
|
Ethyl acetate |
84 |
|
|
Carbon tetrachloride |
|
22.9 |
|
2-Butanone |
87 |
|
|
Bromobenzene |
|
31 |
|
|
Hexane |
95 |
|
Methoxybenzene |
|
37 |
|
|
Methanol |
98 |
|
Bis(2-ethoxyethyl) ether |
44 |
|
|
Carbon disulfide |
112 |
|
|
Chlorobenzene |
|
45 |
|
|
Bromoethane |
119 |
|
N -Methylaniline |
|
57 |
|
|
Pentane |
130 |
|
p -Cymene |
|
68 |
|
|
2-Methylbutane |
160 |
|
|
|
|
|
|
|
|
|
11.4 |
|
|
SECTION |
11 |
|
|
|
|||
TABLE 11.2 Molecular Lowering of the Melting or Freezing Point |
|
|
|
|
||||||
Cryoscopic constants. |
|
|
|
|
|
|
|
|
|
|
The cryoscopic constant |
gives Ktheƒ depression of the melting point |
|
|
T (in degrees Celsius) produced when 1 |
||||||
mol of solute is dissolved in 1000 g of a solvent. It is applicable only to dilute solutions for which the number |
||||||||||
of moles of solute is negligible in comparison with the number of moles of solvent. It is often used for molecular |
|
|||||||||
weight determinations. |
|
|
|
|
|
|
|
|
|
|
|
|
|
M |
2 |
1000 |
w K2 |
ƒ |
|
||
|
|
|
|
w |
1 T |
|
|
|
||
|
|
|
|
|
|
|
|
|
||
where |
w 1 is the weight of the solvent and |
w 2 is the weight of the solute whose molecular weight is |
M 2 . |
|||||||
|
|
|
|
|
|
|
|
|
|
|
|
Compound |
K ƒ |
|
|
|
|
|
Compound |
K ƒ |
|
|
|
|
|
|
|
|
||||
Acetamide |
|
4.04 |
|
|
Diphenylamine |
8.60 |
||||
Acetic acid |
|
3.90 |
|
|
Diphenyl ether |
7.88 |
||||
Acetone |
|
2.40 |
|
|
1,2-Ethanediamine |
2.43 |
||||
Ammonia |
|
0.957 |
|
|
Ethoxybenzene |
7.15 |
||||
Aniline |
|
5.87 |
|
|
|
Formamide |
3.85 |
|||
Antimony(III) chloride |
|
17.95 |
|
Formic acid |
2.77 |
|||||
Benzene |
|
5.12 |
|
|
|
Glycerol |
3.3 to 3.7 |
|||
Benzonitrile |
|
5.34 |
|
|
|
Hexamethylphosphoramide |
6.93 |
|||
Benzophenone |
|
9.8 |
|
|
|
|
|
|
|
|
Bicyclohexane |
|
14.52 |
|
|
|
N -Methylacetamide |
6.65 |
|||
Biphenyl |
|
8.0 |
|
|
|
2-Methyl-2-butanol |
10.4 |
|||
Borneol |
|
35.8 |
|
|
|
Methylcyclohexane |
14.13 |
|||
Bornylamine |
|
40.6 |
|
|
|
Methyl |
|
cis -9-octadecenoate |
3.4 |
|
Butanedinitrile |
|
18.26 |
|
|
|
2-Methyl-2-propanol |
8.37 |
|||
Camphene |
|
31.08 |
Naphthalene |
|
|
6.94 |
||||
Camphoquinone |
|
45.7 |
|
Nitrobenzene |
6.852 |
|||||
D -( )-Camphor |
|
39.7 |
|
Octadecanoic acid |
4.50 |
|||||
Carbon tetrachloride |
|
29.8 |
|
2-Oxohexamethyleneimine |
7.30 |
|||||
o -Cresol |
|
5.60 |
|
|
|
Phenol |
|
|
7.40 |
|
p -Cresol |
|
6.96 |
|
|
|
Pyridine |
4.75 |
|||
Cyclohexane |
|
20.0 |
|
Quinoline |
|
|
1.95 |
|||
Cyclohexanol |
|
39.3 |
|
Succinonitrile |
18.26 |
|||||
Cyclohexylcyclohexane |
|
14.52 |
Sulfuric acid |
1.86 |
||||||
Cyclopentadecanone |
|
21.3 |
1,1,2,2-Tetrabromoethane |
21.7 |
||||||
cis -Decahydronaphthalene |
|
19.47 |
1,1,2,2-Tetrachloro- |
|
||||||
trans |
-Decahydronaphthalene |
20.81 |
|
1,2-difluoroethane |
37.7 |
|||||
Dibenz[ de ,kl ]anthracene |
25.7 |
|
|
|
Tetramethylene sulfone |
64.1 |
||||
Dibenzyl ether |
|
6.27 |
|
|
|
p -Toluidine |
5.372 |
|||
1,2-Dibromoethane |
|
12.5 |
Tribromomethane |
14.4 |
||||||
Diethyl ether |
|
1.79 |
|
|
1,3,3-Trimethyl-2-oxabicyclo- |
|
||||
1,2-Dimethoxybenzene |
|
6.38 |
|
[2.2.2.]octane |
6.7 |
|||||
N,N |
-Dimethylacetamide |
|
4.46 |
|
Triphenylmethane |
12.45 |
||||
2,2-Dimethyl-1-propanol |
|
11.0 |
Water |
|
|
1.86 |
||||
Dimethyl sulfoxide |
|
4.07 |
|
|
|
p -Xylene |
4.3 |
|||
1,4-Dioxane |
|
4.63 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|